[ovs-dev] [PATCH] rhel: Fix literal dollar sign usage in systemd service files

Timothy Redaelli tredaelli at redhat.com
Mon Apr 16 15:15:47 UTC 2018

Currently (at least on RHEL 7.5) openvswitch fails to start (with DPDK
enabled) as non-root, since chown fails and "/dev/hugepages" group is not

Commit tested on Fedora 28 and RHEL 7.5, both as root as non-root user.

>From man 5 systemd.service:

  To pass a literal dollar sign, use "$$". Variables whose value is not known
  at expansion time are treated as empty strings. Note that the first argument
  (i.e. the program to execute) may not be a variable.

CC: Aaron Conole <aconole at redhat.com>
Fixes: 4299145c1095 ("rhel: don't drop capabilities when running as root")
Signed-off-by: Timothy Redaelli <tredaelli at redhat.com>
 rhel/usr_lib_systemd_system_ovs-vswitchd.service.in | 2 +-
 rhel/usr_lib_systemd_system_ovsdb-server.service    | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/rhel/usr_lib_systemd_system_ovs-vswitchd.service.in b/rhel/usr_lib_systemd_system_ovs-vswitchd.service.in
index 889740f1a..11b34c686 100644
--- a/rhel/usr_lib_systemd_system_ovs-vswitchd.service.in
+++ b/rhel/usr_lib_systemd_system_ovs-vswitchd.service.in
@@ -15,7 +15,7 @@ EnvironmentFile=/etc/openvswitch/default.conf
-ExecStartPre=-/bin/sh -c '/usr/bin/chown :${OVS_USER_ID##*:} /dev/hugepages'
+ExecStartPre=-/bin/sh -c '/usr/bin/chown :$${OVS_USER_ID##*:} /dev/hugepages'
 ExecStartPre=-/usr/bin/chmod 0775 /dev/hugepages
 ExecStart=/usr/share/openvswitch/scripts/ovs-ctl \
diff --git a/rhel/usr_lib_systemd_system_ovsdb-server.service b/rhel/usr_lib_systemd_system_ovsdb-server.service
index e05742d87..0fa57a925 100644
--- a/rhel/usr_lib_systemd_system_ovsdb-server.service
+++ b/rhel/usr_lib_systemd_system_ovsdb-server.service
@@ -11,7 +11,7 @@ Restart=on-failure
 ExecStartPre=/usr/bin/chown ${OVS_USER_ID} /var/run/openvswitch
-ExecStartPre=/bin/sh -c 'rm -f /run/openvswitch/useropts; if [ "${OVS_USER_ID/:*/}" != "root" ]; then /usr/bin/echo "OVSUSER=--ovs-user=${OVS_USER_ID}" > /run/openvswitch/useropts; fi'
+ExecStartPre=/bin/sh -c 'rm -f /run/openvswitch/useropts; if [ "$${OVS_USER_ID/:*/}" != "root" ]; then /usr/bin/echo "OVSUSER=--ovs-user=${OVS_USER_ID}" > /run/openvswitch/useropts; fi'
 ExecStart=/usr/share/openvswitch/scripts/ovs-ctl \
           --no-ovs-vswitchd --no-monitor --system-id=random \

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